{"instruction": "You are an expert in named entity recognition. Please extract entities that match the schema definition from the input. Return an empty list if the entity type does not exist. Please respond in the format of a JSON string.", "schema": ["Chemical", "Disease"], "input": "Following a 3 - week observation period , volunteers were treated with zidovudine 600 mg / day for 18 weeks , 900 mg / day for 9 weeks and 1200 mg / day for 9 weeks , followed by a washout period of 6 weeks after which they were re - started on 1200 mg / day or the highest tolerated dose at 8 - hourly intervals ."}
{"Chemical": ["zidovudine"], "Disease": []}